Shearing device



Jam 7, 1936.

A. B. HARRIS 2,026,630

SHEARING DEVICE Filed June 19, 1935 Har/vis. BY ff MMM.

ATTORNEY I' UNITED-f My invention relates to shearing, devices and moreparticularly to those of the vrotary type wherein a cutter is rotatablymounted within a guard and has for its principal object to provide amore elcient cutter construction. that retains use.

Other important objects of the invention are to provide for automatic,self-tensioning of a cutter relatively to its guard, to provide'flexible' coupling of the cutter with its driving shaft, to provide` aflexible cutter to freely accommodate .itself to theguard, to provide anextended cutting surface between the cutter and the teeth of the guardand to provideu a self-clearingy cutter construction whereby the cut.material is expelled from the guard.

In accomplishing these and other objects of the invention, I haveprovided improved details of 0 structure, the preferred forms of whichare illustrated in the accompanying drawing, wherein:

Fi'g. v1 is a perspective view of a shearing device constructed inaccordance with my invention.

Fig. 2 is a similar view showing the parts of the Y shearing device indisassembled spaced relation to better illustrate their construction.

Fig. 3l is an enlarged, longitudinal, section through the device.

-4 is an enlarged cross-sectional view 30 throughguard and cutter on theline 4 4, Fig..3.

mentary portion of the cutter, particularly illustrating the cuttingteeth thereon. Fig. 6 -is a cross-sectional viewthrough amodigfedformofguard.

modified form of guard. Referring more in detail to the drawing:

I designates anelectric motor, preferably of by which the shearingdevice may be readily manipulated, as later described. In theillustrated instance, the motor includes a cylindrical housing 2enclosing the motor mechanismindicated by the armatureshaft 3 and aswitch 4 for controlling current to the motor which is supplied from' anordinary light socket through the'wires. The

end of the armature shaft 3 is tubularf-and'projects from the end of thein'otor housing to form r 'a base flange l provided with openings 3through 5 5 as j PATENT oFFlcE '."aozaoff f f A, 'snnannvonnvicn- I lmie n nm'iaxmscuaml Applicationiune 1933,l SerialNm 676,507

Fig. 5 is an enlarged, perspectiveview of a fragsuitable shape anddimensions to form a handle l a drive connection for the cutter,l m-mirmSie?? which screws 3 are extended to the brglet tothe end of the motorhousing in axial alignment with'the shaft 3.-4 The bracket 6 also'includes a truncated cone-shaped neck portion In Vprovided with internalthreads II to mount a bracket extension I2. f

. The extension I2 includes a cone-shaped body portion I3 having areduced threaded shank' I4 forming an annular stop4 shoulder I5 with thei lbody portion. The outer end of the body' portion terminates in acylindrical neck I6 having exter- 10 nal threads I1 for described.

The shank I4 o'f the bracket extension isA threadedly` engaged `in thethreads vI'I of the bracket and the shoulder I5- thereof is drawn intol5 engagement with the endface I9 of the bracket to prevent rotation ofthe extension when the cutter is in operation.

The cutter. guard I8 includes a hollow truncated sleeve portion having`an intemally 20 threaded 'cylindrical base 2| mounted on the threadedneck I6 of the bracket extension and which is retained againstrotationthereon by a ring type lock nut 22 having internal threads 23 mountingthe guard I8. later arranged for frictionally engaging the end face v25of the guard, as clearlyshown in' Fig. 3. The outer periphery of "thellock nut is preferably knurled, asat 2 6, so that itinay be readilygrasped i Y by the ngers and-moved into tight relation with the end ofthe guard after adjustment thereof relatively to the cutter, as laterdescribed.

The forward portion 20 iof the guard is provided with a4 cone shapedbo're 21 in which is ro- Y tatably mounted the cutter 28 and which has a35 I Fig. 7 is a cross-sectional view throughanother terial cut bytheshearlng device.

series ofopenings 29 -to forx'n outlets for the ma- 1 The conicalportion of the guard is provided on the side opposite. the openings 29with a series teeth 3I extendin'gln angular relation tothe axis of theguard to form angular-cutting faces v32 on 'the side edge thereof in thedirection of the motor to. cooperate with the blade 'of the cuttei toprovide a shearing cut', as laterdescribed; The 45 side ofthe guardcarrying-the teeth is preferably reduced in thickness at the center ofthe teeth, as at33, and the ends of the teeth are of increased thicknesstoward their base,` as at 34 and $5 where they join thebody or backportion 36 50 of the guard, as clearly iiiustrated in` Fig. 4g vFormedonthe surface ,of the 4guard-at opposite sides of the thinnest portionof the teeth are spaced longitudinal ribs `or combs"4 31 and 33 fomSupports forengaging the .surfaceover 'for receiving the threads I1 andhaving its end 24 25 of annularly arranged slots 30 forming spaced 40which the shearing device is moved, as later described. to comb the cutmaterial into cutting relation with the teeth and to gauge the degree ofcut afforded by the cutter. In the case of a razor. the combs alsopermit the skinl to cup upwardly therebetween so that a close shave isafforded.

'I'he cutter 29 includes a conical spiral ribbon 39 conforming indiameter and taper to the inner conical bore of .the guard, so that theouter peripheries 40 of the spiral move in sliding contact with theinner face 4I'of the guard teeth` and across the cutting edges 32 uponrotation of the spiral. The base 42 of the spiral terminates in a seriesof closely wound coils 43 having -internal threads 44 by which thecutter is mount- "ed on a flexible drive member 46, as now to bedescribed.

The drive member 46 includes a exible shaft 2o portion 41 extendingthrough an axial bore 48 in the bracket extension I2 and has its innerend provided with a. slotted coupling member 49 re.`

ceived within the tubular end of the armature shaft 3. The slot in thecoupling engages a pin 25 50 having its ends mounted in the oppositewalls of the 4shaft to provide a driving connection between the armatureand the flexible portion of the driving member.

The opposite end of the driving shaft carries a threaded head 52 fixedsecurely thereon and having external threads 53 for engaging the threads44 of the cutter and having an annular collar or shoulder portion 54 fortightly engaging the end face of the rst of the coils 43 so that whenthe cutter is threaded on the head, the

ange 54 thereof will prevent rotation of the cutter independently of therotation of the shaft.

In order to prevent longitudinal movement of ,the cutter and its driveshaft relatively to the motor, the flexible portion of the drive shaftis provided with a sleeve 55 fixed thereto at a point within an enlargedportion 56 of the bore 48.

The sleeve 55 carries an annular flange 51 of suitable\diameter to bereceived in the enlarged portion of the bore to be anchored betweenspaced anti-friction bearing sets 58 and 59 having their opposite sidesrespectively engaging the end 60 of an enlarged portion of the bore anda washer 6| slidable on the sleeve at the end adjacent the motor. l

'I'he washer 6I is retained snugly against the bearing set 54 and thebearing set`58 against' the shoulder 60 by a coil spring 62 coiled aboutthe exible portion of the shaft and having one end bearing against thewasher 6i and its oppo-l site end against the sleeve 63 threaded in theend of the bore for adjusting tension of the Spring- It is thus apparentthat when the bearing sets 58 and 59 are in position and retained by thespring and threaded sleeve 63, the driving member is prevented frommovement in either direction relatively to the bracket extension. Thespiral cutter will, therefore, be retained in xed relation relatively tothe guard 2U to maintain the'desired contact between the .cutter and theinner surface of the guard.

In order to enhance the cutting properties of the spiral cutter, theinnerface thereof is preferably provided with a series of V-shaped teethor ribs 64 which cooperate with the periphery of the spiral to form aseries of serrated teeth 65 along the cutting edge thereof.l 'I'hetrailing portion of the spiral ribbon is preferably reduced in di- 475ameter from substantially the center thereof, as

indicated at 68, so that only a narrow portion 61 is in contact with theguard. This is an important feature for the reason that as the ribbonwears relatively to the guard, the teeth 65 will retain their shape dueto the fact that wear has 5 no effect other than shortening the lengthof the ribs 64. f

In order to prevent cut material from being emitted through the end ofthe guard the opening therein is closed by a suitable cap 69 having 10 arounded portion to prevent injury to the surface being sheared by thesharp terminal edge of the guard.

In Fig. 6 is illustrated a modied form of the invention, wherein thetoothed edge 68 of the 15 spiral cooperates with a cutting edge 10 onthe guard 1| so that the material cut by the guard is not only cut alongthe sides of the teeth, as in the preferred form, but against the endsof the cutting edge 10 as well. 20

The form of cutter illustrated in Fig. 7 is substantially the sameasthat illustrated in Fig. 6, except that the teeth extend at right anglesto the axis of the cutterand the. guard is provided with a slot 12 foraccommodating the hair or 25 material to be cut.

Since the guards shown in Figs. 6 and 7 operate against cutting edges10, it is necessary to provide only one rib or comb 31 for gauging theamount of cut of the shearing device. 30

In using the preferred form of the device` constructed and assembled asdescribed, tlreguard is moved angularly back and forth across' thesurface being sheared in the direction of the teeth, so that the ribsact as a comb and the hair. 35 enters between the teeth to be shearedoff by the spiral cutter as the nights thereof move across vthe cuttingedges of the teeth.

When cut, the hairs are expelled through the openingsv 29 spirals.

To tighten the shearing tension of the cutter relatively to the guard,the ring 22 is loosened by slackening it from the end of the guard.

The guard is then moved retractively toward 45 the direction of themotor to cause the cutter to enter farther into the conical bore of theguard. 'Ihe spiral form of the'cutter provides4 suiicient inherenttension to retain the -teeth thereof in ,proper cutting relation withthe. teeth of the 50.

guard. When the proper adjustment is made, the ring 22 is retightenedagainst the guard Ato prevent rotation thereof on the bracket extension.Owing to the ribs or combs 31 and 33, a very close cut is aorded becausepressure of the 55 guard against the surface being sheared presses thesurface upwardly therebetweenin close contact with the cutting edge ofthe'cutter'.'

'Ihe forms of the invention illustrated in Figs. 6 and 7 are used inlike manner except that they 60 .are moved in a single direction acrossthe surface being sheared since they cut only against the cutting edges1U.

' What I claim and desire to secure by Letters Patent is: A, f

1. In a device of thecharacter described. a guard support, a toothedguard on the support. a cutter including a flexible helical ribbonrotatable within the guard and having teeth cooperating with the teethof the guard. and means ro- 70 tatably mounted in the guard support forrotating the cutter.

2. In a device of the character described, a support, a tapered tubularguard adjustably mounted on the support having angularly arranged by thepropelling action of the 4u teeth, a helical ribbon-like cutter a seriesoi' closely wound coils terminating in nights rotatable within the guardabout the axis of said the support and having a series of spaced slotsforming teeth, a helical ribbon-like cutter having a series of closelywound coils lterminating in nights rotatable within the guard about theaxis of said nights and in shearing contact with said teeth, a headmounting said closely wound coils of the cutter, means mounting the headin the guard support. and means for rotating the head.

4. In a device of the character described, a guard support, a guardmounted on the support and having a series of spaced slots to formteeth, a helical ribbon-like cutter having a series of closely woundcoils terminating in nights rotatable within the guard about the axis ofsaid nights and in shearing contact with said teeth, a head mountingsaid closely wound coils of the cutter. means mounting the head in theguard support, and means for rotating the head.

5. In a device of the character described, a support, a guard nxed onthe support, a cutter rotatably mounted in the guard including a singienxible ribbon coiled to form a helical cutting edge having free movementlaterally from the longitudinal axis of said cutter whereby the helicalcutting edge is maintained in cooperative cutting contact with theguard, and means connected with the support for rotating the cutter.

6. In a device of the character described, a support, a tapered tubularguard nxed to the support and having teeth, a cutter rotatably mountedin the guard including a single nexible ribbon coiled to form a helicalcutting edge having i'ree movement laterally from the longitudinal axisof said cutter whereby the helial cutting edge is maintained incooperative cuttingeontact with the teeth of the guard, and meansconnected with the support for rotating the cutter.

,7. In a device of the character described, a

support, a toothed tubular guard nxed on the A y support, a cutterrotatably mounted on the guard Yincluding a single nexible ribbon coiledto form a helical cutting edge having free movement laterally relativelyto the longitudinal axis o! said cutter, whereby the helical cuttingedge is maintained in cooperative cutting contact with the 5 guard,means for regulating said cutting contact, the means connected to thesupport for rotating the cutter.

8. In a device of the character described, a

support, a tubular guard member nxed on the 10 support, a cutter memberrotatably mounted in" the guard including a single nexible ribbon coiledto form a helical cutting edge having cooperative cutting contact withthe guard, means for ad- Justing one o! said members relatively to thel5 other to vary pressure of said contact, and means connected with thesupport for rotating the cutter member.

9. In a device ot the character described, a support, a tapered tubularguard adjustably mount- 2ov cai ribbon forming a nexible'cutter havingnights rotatable within the guard about the axis of said 35v nights andretained in shearing contact with said teeth incidental to nexibility ofthe cutter, and ilexible means mounting the cutter for bearing supportin the guard.

l1. In a device of the character described, a 40 support, a tubularguard nxed on the support and

